Energy-saving power adapter/charger

ABSTRACT

An embodiment of the present invention is directed to a power device for an electronic device, such as a charger for a portable rechargeable device and/or an AC adapter. The power device includes switching circuitry for de-powering at least a portion of the power device when the electronic device is either not drawing power or is disconnected from the power device.

FIELD OF THE INVENTION

The invention relates to power devices and, in particular, to powerdevices having an automatic shut-off feature to reduce or eliminateuseless power draw from an outlet and, more particularly, to automaticshut-off power adapters and/or chargers removably connectable toelectronic devices for powering by the adapters/chargers.

BACKGROUND

Many portable electronic devices exist today for consumers. In fact,many consumers carry multiple portable devices such as music players,cellular telephones, personal data assistants, smartphones such as thosemarketed as a Blackberry by Research In Motion, Inc., portable globalpositioning system devices, etc. These portable devices are powered by arechargeable, on-board battery.

In order to charge the battery, the portable device (or possibly justthe battery thereof) is connected to a power device. Typically, thepower device is a combination of a charger and a power adapter so thatalternating current with an input voltage is received and converted todirect current, and the voltage is stepped-down to an output voltage forwhich the battery is designed. It should be noted that, depending onsource power and output power requirements, the power device need notalways convert and step, instead being able to do one or the other, suchas may be the case for a DC-DC adapter used only to step-down the inputvoltage to an output voltage or simply receiving input power anddelivering output power to the battery.

The power device typically has a first end with a pair of prongs thatare received in and connected to a receptacle of a power outlet, and hasa cable extending from the first end to a second end, the second endhaving a connector for electrical connection with the portable device.The power device also typically includes internal circuitry for thepower conversion and stepping, and this circuitry requires an enlargedportion (enlarged relative to the cable of the power device). Theenlarged portion is typically located at or adjacent the first end,though it may be inline and between the first and second ends or belocated at the second end such as in a desktop-style or cradle-typecharger.

Regardless of the configuration, the usage of the power device is almostuniformly identical. Specifically, a user connects the first,prong-bearing end of the power device with a receptacle, such as areceptacle of a wall-oriented/mounted power outlet. The power devicesecond end is placed in a convenient place for the user to reach, andthe portable device is connected to the second end when recharging isneeded or desired, commonly on a daily basis at the end of a day. Whenthe user desires to use or carry it, the portable device is disconnectedfrom the power device, and the second end is left in the convenientplace. Rarely, if ever, does the user think to unplug the power devicefrom the receptacle. One of the reasons for this is that receptacles aretypically behind furniture or in another location that is difficult toreach, or it is just too much trouble to unplug when it is known that itwill need to be plugged in again a relatively short period of time.

There is a growing but still largely unappreciated recognition by usersthat leaving the power device plugged in allows the power device tocontinue to draw current or power from the receptacle despite noportable device being connected therewith. This power draw is referredto as phantom load. To be more precise, phantom load is residual powerconsumption by power devices when not connected to their host electronicdevice, or when the electronic device is shut off.

Phantom load is becoming a greater issue for the public. Electricaldevices that result in the described phantom load are continuallyincreasing in per capita usage, populations increase exponentially, andgreat portions of the world's population are gaining the discretionarycapital that enables the purchase of such devices. Energy is becomingmore expensive on a monetary basis, and energy production overwhelminglyhas an environmental impact, such as fossil fuel or nuclear energy.

Extensive effort has been and continues to be put into development ofenergy-efficient devices of all sorts. The “Energy Star” programsponsored by the United States Environmental Protection Agency and theUnited States Department of Energy is well known, though principally forenergy efficiency appliances and building products such as glass doorsand windows. In parallel with Energy Star standards efforts, a varietyof state and federal laws have been enacted that are directed towardexternal power-supply products, which includes power devices or chargersfor portable electronic devices. The most-recent standard for suchportable devices is version 2.0 and is considered a push beyond simplyforcing the industry to use power efficient components and layouts,requiring more complex power devices and supplies.

A recent development that arose during the preparation of the presentapplication is a prototype device from Nokia that operates with amechanical switch. Specifically, the Nokia device has a first endreceivable in a power receptacle and including a housing for internalcircuitry that provides the charger/adapter functions. The Nokia deviceis turned on by depressing a button on the housing; when the internalcircuitry recognizes the electronic device is fully charged, the buttonis released and the Nokia device is turned off.

While it is believed to have been developed after conception of theinvention of present application, the Nokia device highlights someinteresting points about efforts in this arena. For instance, the buttonof the Nokia device is a mechanical button and requires some type ofmechanism for releasing the button for the “off” state. The button isalso located on a housing for the internal circuitry that is separatefrom the electronic device connector, the connector being a two-terminaldevice (that is, having “+” and “−” terminals). The Nokia device alsorequires some type of mechanism for determining when the device shouldbe shut down.

As discussed above, most people do not bother to unplug their powerdevices when they remove the portable electronic device therefrom. TheNokia device certainly relieves a user from having to plug and un-plugthe device, but it still requires a user to reach to wherever the deviceis received in a receptacle in order to turn on the device.

In order to be a true “zero-energy” device, the power input (i.e., ACinput) to the power device must be cut. That is, the point in the powerdevice circuitry where the circuit is broke is important: a switch orthe like simply on a end-point terminal of the power device may cut thepower being delivered to an electronic device connected thereto that isfully charged, but, such allows the internal circuitry to draw power sothat the effect of such would be no different than simply removing theelectronic device itself.

Towards this end, the Nokia device displays a uniform manner of thinkingin the industry: a switch for connecting or disconnecting the AC powermust be co-located with or closely proximate to the AC input such as thepower prongs.

Accordingly, it is desirable and there is a need for an improved powerdevice, charger or otherwise, for reducing phantom load when a portableelectrical device is disconnected from the power device or otherwise notintended to be drawing power from the power device.

SUMMARY

In a first aspect, a power device for supplying power to a portablerechargeable electronic device is disclosed including a first portionfor receiving electrical input power from a source, the input having aninput voltage, a second portion for delivering electrical output powerto the electronic device, the output power having an output voltage, aconnector located on the second portion and removably connectable withthe electronic device, and a switch assembly located remote from thefirst portion, the switch assembly having a member movable to andbetween first and second positions corresponding to respective “on” and“off” states, wherein the power device receives the input power in the“on” state, and the power device draws no input power in the “off”state.

In a form, the switch assembly member is a throw. In some forms, thethrow may be a toggle or rocker throw.

In some forms, the switch assembly member is a sheath longitudinallymovable to and between the first and second positions.

In some forms, the switch assembly member is manually movable to boththe first and second positions by a user.

In some forms, the power device further includes a cable extendingbetween the first portion and the second portion, and the first portionincludes first and second prongs for electrical communication with areceptacle of a power outlet, circuitry electrically connected to theprongs and to the cable for changing the input power to the outputpower, and a housing from which the prongs and cable extend, thecircuitry disposed within the housing, and the cable includes a firstpair of wires for delivering power to the electronic device and a secondpair of wires for communicating with the switch assembly. The secondpair of wires may be connected such that the switch in the secondposition disconnects a prong from at least a portion of the circuitry toprevent power from being drawn by the power device. The switch assemblymay be located proximate the second portion and connector thereof.

In another aspect, a power device for supplying power to a portablerechargeable electronic device is disclosed including a first portionfor receiving electrical input power from a source, the input having aninput voltage, a second portion for delivering electrical output powerto the electronic device, the output power having an output voltage,circuitry for converting the input power voltage to the output powervoltage and for determining an “off” state of the circuitry, a connectorlocated on the second portion and removably connectable with theelectronic device, and a switch assembly having powered terminals, theswitch assembly responsive to movement of at least a movable portionthereof to electrically connect the terminals and to provide an outputsignal to activate the circuitry to the “on” state, wherein thecircuitry automatically turns the circuitry to the “off” state, thecircuitry drawing no power when in the “off” state.

In some forms, the switch assembly movable portion is biased to a firstposition and is movable to a second position by force applied by theuser, cessation of the force permitting the movable portion to return tothe first position, the switch assembly producing the output signal onlywhen in the second position.

In some forms, the switch assembly movable portion is a pushbuttonspring-biased to a first position and is movable to a second position byforce applied by the user, the pushbutton in the second positionelectrically connecting the terminals to produce the output signal, theoutput signal being a momentary signal from a momentary connection ofthe terminals, and releasing the pushbutton permits return thereof tothe first position.

In some forms, the switch assembly movable portion is anorientation-dependent switch.

In some forms, the switch assembly movable portion is a motion-sensingswitch.

In some forms, the circuitry includes a timer programmed with apredetermined time period, the timer providing a timer signal to thecircuitry at the conclusion of the time period, and the circuitryautomatically changes to the “off” state in response to the timersignal.

In some forms, the circuitry includes a power sensing portion programmedwith a predetermined threshold power level, wherein the circuitryautomatically changes to the “off” state in response to the output powerbeing at or below the threshold power level.

In some forms, the circuitry includes a latching relay that is closed inresponse to the switch assembly output signal, the latching relay beingopened in response to the output power being at or below a thresholdpower level to change the circuitry to the “off” state.

In some forms, the circuitry includes a solid state switch element thatopens in response to the output power being at or below a thresholdpower level to change the circuitry to the “off” state.

In some forms, the switch assembly is located remote from the firstportion. The switch assembly may be located proximate the secondportion.

In a further aspect, a power device for supplying power to a portablerechargeable electronic device is disclosed including a first portionfor receiving electrical input power from a source, the input having aninput voltage, a second portion for delivering electrical output powerto the electronic device, the output power having an output voltage,circuitry for converting the input power voltage to the output powervoltage and for determining an “off” state of the circuitry, a connectorlocated on the second portion and removably connectable with theelectronic device, and a switch assembly located remote from the firstportion and having powered terminals, the switch assembly responsive tomovement of at least a movable portion thereof to electrically connectthe terminals and activate the circuitry to the “on” state, wherein thecircuitry automatically turns the circuitry to the “off” state, thecircuitry drawing no power when in the “off” state.

In some forms, circuitry includes a timer programmed with apredetermined time period, the timer providing a timer signal to thecircuitry at the conclusion of the time period, and the circuitryautomatically changes to the “off” state in response to the timersignal.

In some forms, the circuitry includes a power sensing portion programmedwith a predetermined threshold power level, wherein the circuitryautomatically changes to the “off” state in response to the output powerbeing at or below the threshold power level.

In some forms, the switch assembly provides an output signal to activatethe circuitry to the “on” state, and the circuitry includes a latchingrelay that is closed in response to the switch assembly output signal,the latching relay being opened in response to the output power being ator below a threshold power level to change the circuitry to the “off”state.

In some forms, the circuitry includes a solid state switch element thatopens in response to the output power being at or below a thresholdpower level to change the circuitry to the “off” state.

In an additional aspect, a power device for supplying power to aportable rechargeable electronic device is disclosed including a firstportion for receiving electrical input power from a source, the inputhaving an input voltage, a second portion for delivering electricaloutput power to the electronic device, the output power having an outputvoltage, circuitry for converting the input power voltage to the outputpower voltage and for determining an “off” state of the circuitry, aconnector located on the second portion and removably connectable withthe electronic device, and a switch assembly having powered terminals tochange the circuitry to the “on” state, wherein the circuitryautomatically turns the circuitry to the “off” state, the circuitrydrawing no power when in the “off” state.

In some forms, the switch assembly movable portion is biased to a firstposition and is movable to a second position by force applied by theuser to change the circuitry to the “on” state. Cessation of the forcemay permit the movable portion to return to the first position.

In some forms, the circuitry includes a timer programmed with apredetermined time period, the timer providing a timer signal to thecircuitry at the conclusion of the time period, and the circuitryautomatically changes to the “off” state in response to the timersignal.

In some forms, the circuitry includes a power sensing portion programmedwith a predetermined threshold power level, wherein the circuitryautomatically changes to the “off” state in response to the output powerbeing at or below the threshold power level.

In some forms, the circuitry includes a latching relay that is closed inresponse to the switch assembly changing the circuitry to the “on”state, the latching relay being opened in response to the output powerbeing at or below a threshold power level to change the circuitry to the“off” state.

In some forms, the circuitry includes a solid state switch element thatopens in response to the output power being at or below a thresholdpower level to change the circuitry to the “off” state.

In some forms, the switch assembly is located remote from the firstportion.

In some forms, the switch assembly is located proximate the secondportion.

BRIEF DESCRIPTION OF THE DRAWINGS

In the Figures, FIG. 1 is a partially fragmentary view of a first formof a power device of the present invention, the power device having afirst end for connecting with a power source, a second end forconnecting with an electrical device, and an in-line two-positionswitch;

FIG. 2 is a fragmentary view of the power device of FIG. 1 showing linedesignations for wires of a cable of the power device;

FIG. 3 is a simplified circuit diagram for the fragmentary portion ofthe power device of FIG. 2;

FIG. 4 is a representational view of a cross-section of a first form ofthe cable of the power device of FIG. 1;

FIG. 5 is a representational view of a cross-section of second form ofthe cable of the power device of FIG. 1;

FIG. 6 is a representational view of a form of the power deviceincluding an outer sheath positioned proximate a connector, the sheathbeing movable to and between first and second positions, the sheathbeing in a first position when the connector is not connected to anelectrical device and in a second, retracted position relative to theconnector when the connector is joined with an electronic device, thesecond position causing an electrical circuit to be closed;

FIG. 7 is a representational view of a form of the power deviceincluding a mechanically actuated switch, which may also include anintegrated circuit coupled with the mechanically actuated switch;

FIG. 8 is a circuit diagram illustrating aspects of different forms of apower device of the current invention;

FIG. 9 is a partial circuit diagram showing an optional form of internalcircuitry including a relay switch;

FIG. 10 is a circuit diagram of an exemplary form of the power deviceshowing a switch provided to open the circuit at or proximate one ofprongs to prevent power from being drawn by the power device;

FIG. 11 is a circuit diagram of an exemplary form of the power deviceshowing a power-on or activating switch, such as a solid state switch, aportion of the circuit monitoring the transformer secondary pulses tocreate a voltage proportional to the load current to drive anauto-shutoff switch;

FIG. 12 is a circuit diagram of an exemplary form of the power deviceshowing an electromechanical relay provided to open and close thecircuit at or proximate one of prongs to prevent power from being drawnby the power device, the electromechanical relay being connected with aswitch for activating and closing the relay and the circuit; and

FIG. 13 is a circuit diagram of an exemplary form of the power deviceshowing a switch for determining the state of the power device with acurrent sensing circuit.

DETAILED DESCRIPTION

Generally stated, the present invention includes a power device, such asa charger or adapter, for providing power to an electrical device thatis designed to shut off or at least reduce power draw from a powersource when the electrical device does not need power. In a more finiteform of the invention, the power device is an AC-DC charger andconverter for a portable rechargeable electronic device that isconnectable with a connector on the power device. In the preferredforms, the power device has a housing co-located at a first end withprongs for connecting with an electrical sources such as an outlet, hasa cable extending from the housing to a second end, and has theconnector located at the second end for connecting with the portableelectronic device. In a more preferred form, the second end includesswitch components for switching the power device from an “off” state(when the electronic device is fully-charged or not connected to theconnector) to an “on” state allowing power to be delivered to aconnected electronic device. In one form, the switch components operateto cut power on the AC portion of the internal circuitry of the powerdevice so that the power draw is zero or negligible (i.e., measured inmicrowatts). In another form, the switch components operate to initiatea power device “on” state while a timer circuit, a power sense circuitor other circuit means in the power device are used to switch the powerdevice to an “off” state so that the power draw is zero or negligible.

Referring initially to FIGS. 1-3, a relatively basic form of a powerdevice 10 is shown. The power device 10 has a first end 12 forconnection with a receptacle of a power outlet (not shown), the poweroutlet providing electrical power to the power device first end 12 viaprongs 14 that are inserted within the receptacle. The power device 10also has a second end 16 for connecting with a receptacle 21 of anelectronic device 20 (see FIG. 7). The electronic device 20 may be anytype of device that may be connected or disconnected, for example aportable device such as a cellular telephone or music player or the likethat is connected for charging and generally disconnected for use,though these electronic devices 20 are often left connected for longerdurations of time than are necessary for fully charging the electronicdevice 20.

Towards this end, the power device 10 includes electronic circuitry 30,discussed below and shown in FIG. 8, for altering input power from thereceptacle at the prongs 14 to output power delivered to the electronicdevice 20. The circuitry 30 is generally located within a housing 32preferably positioned proximate to the first end 12. For instance, thepower device 10 may receive 120 VAC at the prongs 14 and, afterconversion and stepping, delivers 5 VDC from the ground G and currentoutput D, discussed below.

The power device 10 includes a connector 40 providing the ground G andcurrent output D. In some forms, the connector 40 is directly connectedto the electronic device receptacle 21, though there may also be anintermediate connector 23 (see FIG. 7). The intermediate connector 23includes a receptacle 23 a for receiving the connector 40 and asecondary connector 23 b for receipt into the electronic devicereceptacle 21. In a preferred form, a plurality of intermediateconnectors 23 may be provided, and a user is able to select anintermediate connector 23 for a specific corresponding electronic device20. In this manner, features of the present power device 10 are enabledand supported while still allowing the use of any type of connector 40(and connection with the electronic device 20).

As can be seen in FIGS. 1 and 2, the power device 10 includes a cable 42generally extending between and connected with the housing 32 and theconnector 40. As also can be seen, a switch assembly 50 is providedin-line with the cable 42. In FIG. 1, a preferred form of the connector40 is shown as a mini-USB connector having four wires 44 a-44 d, thoughother connectors 40 (standard or not) may be used, and, as discussedabove, the connector 40 may be used with the intermediate connector 23so that the secondary connector 23 b is provided for use with theelectronic device 20.

As is readily recognized, the switch assembly 50 includes a rocker ortoggle throw 52 having two positions for connecting or disconnectingpower to the connector 40. In a first position, the throw 52 is in an“on” state so that a circuit is closed across switch terminals 50 a and50 b (see FIG. 3), and power is conducted to the electronic device 20when connected to the connector 40, while the throw 52 is in an “off”state when in the second position with the circuit being open acrossterminals 50 a and 50 b and no power is conducted to the electronicdevice 20.

Turning to FIG. 3, it can be seen that cable 42 includes the wires 44a-44 d for, respectively, direct current output D, first live L1, secondlive L2, and ground G, as are known for use with a mini-USB. The livesL1 and L2 are connected to the throw 52 such that they are connectedwhen the throw 52 is in the “on” state, and such that they aredisconnected when the throw 52 is in the “off” state. The output D andground G pass through the switch assembly 50 for connection to theirrespective pins of the mini-USB connector 40. In comparison to FIG. 8showing the entire circuit including the alternating current input atthe prongs 14, the lives L1 and L2 have terminals 100 and 102,respectively, while the output D and ground G are labeled as such andare at the second end 16. When the connector 40 is used with theintermediate connector 23, the secondary connector 23 b thereof needonly be provided with electrical connection with the output D and groundG terminals.

FIG. 3 also shows the wiring of the wires 44 a-44 d, while FIGS. 4 and 5illustrate how the wires 44 a-44 d in a single jacket 46 (FIG. 4) or ina pair of jackets 46 (FIG. 5) separated by a bridge 48 to provideadditional isolation. Preferably, 26 American Wire Gauge (AWG) is usedfor the lives L1 and L2, while 22 AWG may be used for the ground G andoutput D wires. It is preferred that total isolation between the livesL1, L2 and the ground G/output D pairs is minimally 3 kV.

In a preferred form of the power device 10, the switch assembly 50 islocated proximate to the connector 40. In this manner, a user may easilymanually switch the throw 52 between the “on” and “off” states when theelectronic device 20 is connected or removed. In a preferred form, theswitch assembly 50 includes a rocker switch, minimum rated at 2.5 A, towhich the lives L1 and L2 are connected and including the throw 52. Thecable 42 is preferably in the order of 6 feet in length.

More importantly, by utilizing the four-wire form described for thecable 42, the switch assembly 50 opening or closing the switch terminals50 a, 50 b on wires 44 b and 44 c (for the lives L1 and L2) are able tocut power anywhere in the power device 10. In greater detail and withreference to FIG. 8, the power device 10 receives an input power at theprongs 14. The portion of a charger/adapter that is most directlyresponsible for power draw or phantom load are a switcher IC chip 210(see FIG. 8), a transformer T (see FIG. 8), and components downstreamtherefrom. As can be seen in FIGS. 3 and 8, the switch terminals 50 aand 50 b are generally remote from the other circuit components of thepower device 10. However, the wires 44 b and 44 c are connected with thecircuit diagram of FIG. 8 before the transformer T. Therefore, if thecircuit is open across terminals 50 a and 50 b, the power in the powerdevice 10 is cut, the transformer T is unable to draw power, and thephantom load for the power device 10 is virtually eliminated. In analternate form shown also shown in FIG. 8, lives L1′ and L2′ areprovided, substituting for lives L1 and L2 as shown, and are able to cutpower in the power device 10 before the rectifying diode bridge 420 bybeing opened at the switch terminals 50 a and 50 b.

Turning to FIG. 6, a second form of the power device is shown as powerdevice 100, also including a mini-USB connector 140. More specifically,a different form of switch assembly 50 is shown. For simplicity, thepower device 100 is shown having a cable 102 and a second end 104, andit is understood that a first end and circuitry for the power conversionand step down would be incorporated into the power device 100 despitenot being illustrated. In this form, the switch assembly 50 is shown asa sheath 110 provided on a portion of the cable 102. The sheath 110 islongitudinally movable to and between a first position, illustrated indashed lines, and a second position, illustrated in solid lines, whereinthe first and second positions respectively corresponds to the “on” and“off” states discussed above. The sheath 110 is slid rearwardly and awayfrom an end 140 a of the connector 140 when an electronic device 20 isconnected thereto. In so doing, a contact 112 positioned on the sheath110 is moved into electrical connection with first and second terminalsT (also corresponding to terminals 50 a and 50 b in FIGS. 3 and 8) toclose the circuit and allow the power device 100 to deliver power fromthe connector 140. Preferably, the sheath 110 is biased forwardly sothat, when the electronic device 20 is disconnected, the sheath 110automatically turns the power device to the “off” state.

In another form, FIG. 7 illustrates a power device 200 including amechanical motion-sensing switch 202 located proximate a connector 240.In one form, the switch 202 may be a position-dependent switch, such asa mercury switch, so that the switch state (“on” or “off”) is dependenton the orientation of the switch 202 and the connector 240. In anotherform, the switch 202 may be connected to an integrated circuit (IC) 210(see, e.g., FIG. 8) so that, with a brief connection across terminals T,the IC 210 activates the switch 202 to the “on” state. Such briefconnection-type switch 202 may be a mercury switch, may be acantilever-contact switch, or another type of switch.

In some forms, which may or may not be incorporated into the powerdevice 200 of FIG. 7, the IC 210 may control a switch 340 locatedtherein For instance, the IC 210 may include a timer for shifting theswitch 340 to the “off” state, or the IC 210 may control the switch 340in the form of an electromechanical relay or a solid state equivalentsuch as a MOSFET switch, as will be appreciated by one skilled in theart. To return the switch 340 to the “on” state, a number of means maybe employed, such as a mechanical switch depressed briefly by a user, aposition-dependent switch, a quick or brief connection switch thatcommunicates with the IC 210, as mere examples.

In another form using the IC 210 and switch 340, a load sensing device400 may be incorporated within the IC 210, as also shown in FIG. 8. Theload sensing device 400 measures the power or load (i.e., watts oramperage) being drawn from the power device 10. The load is markedlyhigher when the electronic device 20 is connected thereacross anddrawing power than when the electronic device 20 is either removed or ispowered off, or not charging it's battery. Accordingly, the IC 210 andload sensing device 400 recognize power draw or a lack thereof. The IC210 can then open the switch 340 and/or possibly a switch external tothe IC, to cease the current draw when it is recognized that noelectronic device 20 is drawing therefrom. Preferably, such a form forthe IC 210 includes a timer so that a slight pause in power or briefdisconnect between the electronic device 20 and the connector at theground G and output D does not cause the IC 210 to shut the power off byopening the switch 340. As an example, the load sensing device 400senses the pulse width and recognizes how slow or fast the pulse isrepeated to determine the load. As such, when the battery 20 a of theelectronic device 20 ceases to draw power, the power device 10 can becalibrated to switch to the “off” state.

It should be noted that the IC 210 and switch 340 and load sensingdevice 400 may be on-line or off-line and may be in a variety ofconfigurations. As an example, the load sensing device 400 and IC 210may be a pulse-width modulation (PWM) or other type of switch thatcarries its own IC, the PWM device shutting off a portion of the powerdevice 10 while allowing a small portion (such as an incoming diodebridge 420 and input filter capacitors 422, see FIG. 8) to remainpowered by a low current. Pressing a switch (discussed above) can beused to communicate with the small portion (ie., the incoming diodebridge 420 and filter capacitors 422) to re-actuate and power-up thepower device 10. In such a case, the PWM itself is also shut off untilthe power device is re-actuated. Therefore, while the power device 10 isnot completely off, it is in a ultra-low power consumption state and isable to power-up more quickly.

To be more specific with respect to pressing a switch, FIG. 9illustrates portions of a circuit diagram showing such usage andarrangement. In detail, it can be seen that the circuit 500 includes aninput 502 and a rectifying diode bridge 504 that leads to filtercapacitors 506, which in turn lead to an optical isolation coupler 508and nodes 510 for connection to IC 210 and transformer T (see FIG. 8).As can be appreciated, an entire power device circuit is notillustrated, though the other portions of such are shown and describedelsewhere herein, or would be understood by one skilled in the art.

The circuit 500 includes a start switch 520, which may be any type ofswitch for making at least a brief electrical connection. Preferably,the start switch 520 is a push-button switch so that, upon releasing,the contacts of the start switch 520 are disconnected and the startswitch 520 is open. Upon brief electrical connection by the start switch520 (such as by being depressed), a relay electrical contact 530 isconnected. To detail, closing the start switch 520 causes electricalconnection thereacross and, resultingly, powers a relay coil 532. Therelay coil 532 is akin to a solenoid so that it physically moves, thismovement bring the plates 530 a and 530 b of the relay 530 together. Therelay 530 is a latching-type relay so that it remains closed untilotherwise instructed, powered or not. As can be seen, the relay coil 532is connected to the start switch 520 by a closing diode 536 to effectthis; the relay coil 532 is also connected to an opening diode 538 thatis reversed in operation to the closing diode 536. As will be discussed,when the power device 10 recognizes a sufficiently low power draw, atransistor 540 is activated to cause power to flow through the openingdiode 538 and, thus, reverse the physical movement of the relay coil532, which in turn opens the relay plates 530 a, 530 b. In this manner,the power device 10 is returned to its “off” state.

With respect to the above-described sufficiently low power draw, it isnoted that the power device 10 may be calibrated for the amount of loadby an electronic device 20 or amount of load when no electronic device20 is connected. The amount of power being drawn, as discussed above,can be measured by the size and frequency of the pulses. The voltage canbe measured across a capacitor within a circuit that connects to atransformer output winding of the electronic device 20. In one form,when the power load is sufficiently small, the capacitor will drainfaster than the recharging thereof, eventually resulting, in thetransistor 540 being charged to open the relay plates 530 a, 530 b. Inanother form, the capacitor can be connected to a comparator (such as asimple IC) so that the comparator switches to a state that again chargesthe transistor 540.

In other related forms, intermittent monitoring for the presence of theelectronic device 20 may be performed. In one form, for instance, the IC210 and switch 340 may intermittently monitor the load via the loadsensing device 400. For instance, the IC 210 may shut down most of thepower device, yet power up the load sensing 400 periodically (i.e.,every couple minutes) for a fraction of a second to determine if theelectronic device 20 is present (which would be recognized by the loadcharacteristics across the ground G and output D).

As described, various power devices are described having a variety offeatures that may be selected and/or combined within the scope of thepresent invention to provide a means for low-power consumption ofphantom load, or intermittent power consumption, or no powerconsumption. As can be seen, some of these power devices are dependentin operation on the presence or absence of the electronic device, suchas would be best suited for a portable, rechargeable device that isremoved when charged, while others are independent of the presence orabsence of the electronic device, such as would be useful for a computerwhich is commonly left plugged in and connected to a power device (i.e.,power brick) when turned off.

It should be noted that a variety of the features discussed herein maybe combined with other features discussed herein. Towards this end, FIG.8, for instance, shows a number of features which are not necessary forpracticing the invention in all its forms. As described above, FIG. 9 isdirected towards a form of the power device utilizing a relay 530 drivento close the circuit, and FIG. 12 shows a similar form of a circuit forsuch power device utilizing a relay 530′ driven by a relay coil 532′,the relay 530′ being located in the circuit at a position so thatopening the relay 530′ disconnects all power consumption for the powerdevice. FIG. 10 shows a relatively simple circuit architecture in whicha switch 50 connects at or proximate one of the prongs 14 fordisconnecting the input power before the power-consuming components,resulting in a zero current draw. As noted in FIG. 10, the switch 50 maybe integrated into the cable 42 so that the switch 50 is remote from theother circuitry, as has been discussed above. FIG. 11 shows a circuitarchitecture for the power device wherein the Gain and Level Detectionoperates to monitor pulses from a transformer secondary winding SW todrive a Primary Switch in the with a voltage proportional to the loadcurrent. The form of FIG. 11 utilizes a momentary connection at switch50 to activate the power device, via a brief current resulting from theconnection, and Controls operate the Primary Switch as an automaticshut-off feature when the power device is to be turned off, such as dueto the electronic device being charged or disconnected. It should benoted that the Gain and Level Detection, the Control, and the PrimarySwitch may be included in an IC not shown or in the IC shown in the FIG.11. FIG. 13 shows the switch 50 preferably being a solid state switch,and the power device circuit architecture is designed so that uponmomentary connection (including connection and subsequent release) asmall current through the switch 50 is recognized to power on oractivate the device from an “off” state, and current at resistorR_(sense) is recognized by Gain and Level Detection to control thePrimary Switch, voltage below a threshold being used to determine andswitch to an “off” state for the power device.

While the invention has been described with respect to specific examplesincluding presently preferred modes of carrying out the invention, thoseskilled in the art will appreciate that there are numerous variationsand permutations of the above described systems and techniques that fallwithin the spirit and scope of the invention as set forth in theappended claims.

1. A power device for supplying power to a portable rechargeableelectronic device, the power device comprising: a first portion forreceiving electrical input power from a source, the input having aninput voltage; a second portion for delivering electrical output powerto the electronic device, the output power having a DC output voltage; aconnector located on the second portion and removably connectable withthe electronic device; and a switch assembly having a member movable toand between first and second positions corresponding to respective “on”and “off” states of the power device, wherein the power device receivesthe input power in the “on” state, and the power device draws no inputpower in the “off” state.
 2. The power device of claim 1 wherein theswitch assembly member is a throw.
 3. The power device or claim 2wherein the throw is a toggle or rocker throw.
 4. The power device ofclaim 1 wherein the switch assembly member is a sheath longitudinallymovable to and between the first and second positions.
 5. The powerdevice of claim 4, wherein the sheath is biased to the second positionso that, when the electronic device is disconnected from the connector,the sheath automatically turns the power device to the “off” state. 6.The power device of claim 1 wherein switch assembly member is manuallymovable to at least one of the first and second positions by a user. 7.The power device of claim 1 further including a cable extending betweenthe first portion and the second portion, wherein the first portionincludes: first and second prongs for electrical communication with areceptacle of a power outlet; circuitry electrically connected to theprongs and to the cable for changing the input power to the outputpower; and a housing from which the prongs and cable extend, thecircuitry disposed within the housing, wherein the cable includes afirst pair of wires for delivering power to the electronic device and asecond pair of wires for communicating with the switch assembly.
 8. Thepower device of claim 7 wherein the second pair of wires is connectedsuch that the switch in the second position disconnects a prong from atleast a portion of the circuitry to prevent power from being drawn bythe power device.
 9. The power device of claim 7 wherein the switchassembly is located proximate the second portion and connector thereof.10. The power device of claim 1 wherein the switch assembly is locatedon the second portion and longitudinally movable to and between thefirst and second positions, and wherein the switch at least partiallyoverlaps the connector when in the second position.
 11. A power devicefor supplying power to a portable rechargeable electronic device, thepower device comprising: a first portion for receiving electrical inputpower from a source, the input having an input voltage; a second portionfor delivering electrical output power to the electronic device, theoutput power having an output voltage; circuitry for converting theinput power voltage to the output power voltage and for determining an“off” state of the circuitry; a connector located on the second portionand removably connectable with the electronic device; and a switchassembly having powered terminals, the switch assembly responsive tomovement or at least a movable portion thereof to electrically connectthe terminals and to provide an output signal to activate the circuitryto the “on” state, wherein the circuitry automatically turns thecircuitry to the “off” state, the circuitry drawing no power when in the“off” state.
 12. The power device of claim 11 wherein the switchassembly movable portion is biased to a first position and is movable toa second position by force applied by the user, cessation of the forcepermitting the movable portion to return to the first position, theswitch assembly producing the output signal only when in the secondposition.
 13. The power device of claim 11 wherein the switch assemblymovable portion is a pushbutton spring-biased to a first position and ismovable to a second position by force applied by the user, thepushbutton in the second position electrically connecting the terminalsto produce the output signal, the output signal being a momentary signalfrom a momentary connection of the terminals, and releasing thepushbutton permits return thereof to the first position.
 14. The powerdevice of claim 11 wherein the switch assembly movable portion is anorientation-dependent switch.
 15. The power device of claim 11 whereinthe switch assembly movable portion is a motion-sensing switch.
 16. Thepower device of claim 11 wherein the circuitry includes a timerprogrammed with a predetermined time period, the timer providing a timersignal to the circuitry at the conclusion of the time period, and thecircuitry automatically changes to the “off” state in response to thetimer signal.
 17. The power device of claim 11 wherein the circuitryincludes a power sensing portion programmed with a predeterminedthreshold power level, wherein the circuitry automatically changes tothe “off” state in response to the output power being at or below thethreshold power level.
 18. The power device of claim 11 wherein thecircuitry includes a latching relay that is closed in response to theswitch assembly output signal, the latching relay being opened inresponse to the output power being at or below a threshold power levelto change the circuitry to the “off” state.
 19. The power device ofclaim 11 wherein the circuitry includes a solid state switch elementthat opens in response to the output power being at or below a thresholdpower level to change the circuitry to the “off” state.
 20. The powerdevice of claim 11 wherein the switch assembly is located remote fromthe first portion.
 21. The power device of claim 20 wherein the switchassembly is located proximate the second portion.
 22. The power deviceof claim 11 wherein the switch assembly comprises a sheathlongitudinally movable to and between first and second positions,wherein the first position corresponds to the “on” state.
 23. The powerdevice of claim 22, wherein the sheath is biased to the second positionso that, when the electronic device is disconnected from the connector,the sheath automatically turns the power device to the “off” state. 24.A power device for supplying power to an electronic device, the powerdevice comprising: a first portion for receiving electrical input powerfrom a source, the input having an input voltage; a second portion fordelivering electrical output power to the electronic device, the outputpower having an output voltage; power circuitry for converting the inputpower voltage to the output power voltage and for determining an “off”state of the power device; switching circuitry operable to electricallyactivate the power circuitry to the “on” state; and a load sensingportion operable to sense one or more pulses and determine the power orload being drawn from the power device by the electronic device basedthereon.
 25. The power device of claim 24 wherein the switchingcircuitry includes a timer programmed with a predetermined time period,the timer providing a timer signal to the circuitry at the conclusion ofthe time period, and the switching circuitry automatically changes thepower circuitry to the “off” state in response to the timer signal. 26.The power device of claim 24 wherein the load sensing portion isprogrammed with a predetermined threshold level, wherein the switchingcircuitry automatically changes the power circuitry to the “off” statein response to the power or load being drawn from the power device bythe electronic device being at or below the threshold level.
 27. Thepower device of claim 24 wherein the switching circuitry provides anoutput signal to activate the power circuitry to the “on” state, and thepower circuitry includes a latching relay that is closed in response tothe switching circuitry output signal, the latching relay being openedin response to the power or load being drawn from the power device bythe electronic device being at or below a threshold power level tochange the circuitry to the “off” state.
 28. The power device of claim24 wherein the power circuitry includes a solid state switch elementthat opens in response to the power or load being drawn from the powerdevice by the electronic device being at or below a threshold powerlevel to change the circuitry to the “off” state.
 29. The power deviceof claim 24, wherein the load sensing portion determines the power orload being drawn from the power device by the electronic device bymeasuring the size of the pulses.
 30. The power device of claim 24,wherein the load sensing portion determines the power or load beingdrawn from the power device by the electronic device by measuring thefrequency of the pulses.
 31. The power device of claim 24, wherein theload sensing portion measures the pulses electrically on a winding of atransformer of the power device.
 32. The power device of claim 31,wherein the load sensing portion measures the pulses across a capacitorwithin a circuit that connects to the winding of the transformer of thepower device.
 33. The power device of claim 24, wherein the load sensingportion measures the pulses from transformer control circuitry whichcontrols a power state of a transformer of the power device.
 34. Thepower device of claim 33, wherein the transformer control circuitrycomprises switched mode power supply circuitry.
 35. The power device ofclaim 33, wherein the transformer control circuitry comprisespulse-width modulation (PWM) circuitry.
 36. The power device of claim 24further comprising transformer control circuitry for controlling a powerstate of a transformer of the power device, wherein the transformercontrol circuitry and the load sensing portion are incorporated onto asingle integrated circuit.
 37. The power device of claim 24, wherein thecircuitry automatically turns the circuitry to the “off” state, thecircuitry drawing no power when in the “off” state.
 38. The power deviceof claim 24 wherein the switch assembly comprises a sheathlongitudinally movable to and between first and second positions,wherein the first position corresponds to the “on” state.
 39. The powerdevice of claim 38, wherein the sheath is biased to the second positionso that, when the electronic device is disconnected from the connector,the sheath automatically turns the power device to the “off” state. 40.A power device for supplying power to a portable rechargeable electronicdevice, the power device comprising: a first portion for receivingelectrical input power from a source, the input having an input voltage;a second portion for delivering electrical output power to theelectronic device, the output power having an output voltage; powercircuitry for converting the input power voltage to the output powervoltage and for determining an “off” state of the circuitry, the powercircuitry including a switching element; a connector located on thesecond portion and removably connectable with the electronic device; andswitching circuitry, separate from the switching element, having poweredterminals to change the power circuitry to the “on” state by causing theswitching element to close, wherein the power circuitry or switchingcircuitry automatically turns the power circuitry to the “off” state bycausing the switching element to open, the power circuitry drawingsubstantially no power when in the “off” state.
 41. The power device ofclaim 40 wherein the switching circuitry includes a movable portion thatis biased to a first position and is movable to a second position byforce applied by the user to change the circuitry to the “on” state. 42.The power device of claim 41 wherein cessation of the force permits themovable portion to return to the first position.
 43. The power device ofclaim 40 further comprising a timer programmed with a predetermined timeperiod, the timer providing a timer signal to the power circuitry at theconclusion of the time period, and the power circuitry automaticallychanges to the “off” state in response to the timer signal.
 44. Thepower device of claim 40 further comprising a power sensing portionprogrammed with a predetermined threshold power level, wherein the powercircuitry automatically changes to the “off” state in response to theoutput power being at or below the threshold power level.
 45. The powerdevice of claim 40 wherein the switching element comprises a latchingrelay that is closed in response to the switch assembly changing thepower circuitry to the “on” state, the latching relay being opened inresponse to the output power being at or below a threshold power levelto change the circuitry to the “off” state.
 46. The power device ofclaim 40 wherein the switching element comprises a solid state switchelement that opens in response to the output power being at or below athreshold power level to change the power circuitry to the “off” state.47. The power device of claim 40 wherein at least a portion of theswitching circuitry is located remote from the first portion.
 48. Thepower device of claim 40 wherein at least a portion of the switchingcircuitry is located proximate the second portion.
 49. The power deviceof claim 40 wherein the switching circuitry comprises a sheathlongitudinally movable to and between first and second positions,wherein the first position corresponds to the “on” state.
 50. The powerdevice of claim 49, wherein the sheath is biased to the second positionso that, when the electronic device is disconnected from the connector,the sheath automatically turns the power device to the “off” state. 51.A power device for supplying power to an electronic device, the powerdevice comprising: a first portion for receiving electrical input powerfrom a source, the input having an input voltage; a second portion fordelivering electrical output power to the electronic device, the outputpower having a DC output voltage; a connector located on the secondportion and removably connectable with the electronic device; a switchlocated on the second portion and longitudinally movable to and betweenfirst and second positions, the first position corresponding to an “on”state of the power device, wherein the power device receives the inputpower in the “on” state, and wherein the switch at least partiallyoverlaps the connector when in the second position; and wherein thepower device draws substantially no input power in the “off” state. 52.The power device of claim 51, wherein the second position corresponds tothe “off” state of the power device.
 53. The power device of claim 52,wherein the switch is biased to the second position so that, when theelectronic device is disconnected from the connector, the switchautomatically turns the power device to the “off” state.
 54. The powerdevice of claim 51, wherein the switch is biased to the second positionand is movable to the first position by an external force, wherein theswitch returns to the second position upon cessation of the force. 55.The power device of claim 51, wherein the sheath is biased to the secondposition and moves to the first position when the connector is connectedto the electronic device.
 56. A power device for supplying power to aportable rechargeable electronic device, the power device comprising: afirst portion for receiving electrical input power having an inputvoltage from the power outlet, the first portion including: prongs forelectrical communication with a receptacle of a power outlet; convertercircuitry for converting the input voltage into DC output voltage; and ahousing from which the prongs extend, the converter circuitry disposedwithin the housing; a second portion for delivering electrical outputpower to the electronic device, the output power having the DC outputvoltage, and the second portion including a connector located on thesecond portion and removably connectable with the electronic device; aswitch assembly having a member movable to and between first and secondpositions, corresponding to respective an “on” and “off” states of thepower device, wherein the power device receives the input power in the“on” state, and the power device draws no input power in the “off”state; and a cable extending from the housing and between the first andsecond portions, the cable including a first pair of wires fordelivering power to the electronic device and a second pair of wires forcommunicating with the switch assembly.
 57. The power device of claim 56wherein the second pair of wires is connected such that the switch inthe second position disconnects one or more of the prongs from at leasta portion of the converter circuitry to prevent power from being drawnby the power device.
 58. The power device of claim 56 wherein the switchassembly is located proximate the second portion and connector thereof.